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A. E. Grosz

Publications and source records attributed to A. E. Grosz.

36 records · Page 2Linked to original sources

Geochemical survey of the Devil's Den Roadless Area, Rutland and Windsor counties, Vermont

The Devils Den Roadless Area comprises 8,830 acres of mountainous terrane in the Green Mountain National Forest, Rutland and Windsor Counties, Vt. (Index Map). Ludlow, the nearest large community, is approximately 7 air miles northeast of the study area. The small villages of Weston and East Wallingford are 3 to 5 mi to the south and north, respectively. Total relief is nearly 1,200 ft, ranging from a low elevation of 1,640 ft along the southwestern edge of the area, to a high point of about 2,860 ft in the northwest portion. Principal access is provided by state Route 100 and 155 on the southeast and northeast, and by Forest Service Road 10 along the western boundary. Old logging roads and foot trails allow entry to the interior of the study area. Several swamps and one small pond are located in topographically low areas. Drainage is principally to the south and southeast by tributaries of the south-flowing West River, ultimately discharging into the Connecticut River near Brattleboro. The Devils Den area is named for a large undercut cliff (Dale, 1915, p. 21) developed in Precambrian basement rocks. This undercut cliff forms a broad natural cave immediately west of and below Forest Service Road 10, at the head of Mt. Tabor Brook. Another much smaller cave is present in dolomite of probable Paleozoic (Early Cambrian) age on the east side of the same road. This smaller cave apparently is of artificial origin, having been made during early mining of the dolomite (Dale, 1915, p. 21). This man-made cave is the only evidence of previous mining activity within the study area.

Vermont↗

Application of total-count aeroradiometric maps to the exploration for heavy-mineral deposits in the coastal plain of Virginia, with a section on field-spectrometer-data reduction

Total-count contoured aeroradiometric maps for the Coastal Plain of Virginia were used in an effort to locate economic heavy-mineral placer deposits. The principle behind this approach is that heavy- mineral suites commonly contain radioactive minerals that, if the concentration of heavy minerals is exposed at or within inches of the surface, enable the deposit to be located by use of airborne instruments because of its radiometric contrast with the host sediment. Detailed and regional geologic maps, soil maps, land-use and land- cover maps, information on fertilizer use, and ground-spectrometer data were used to study aeroradiometric anomalies for efficient exploration. Aeroradiometric anomalies in the Coastal Plain of Virginia have three general causes. First, the most intense anomalies are associated with cultural features, such as roads made of granitic material. Second, most anomalies of high to intermediate intensity are associated with land used for agricultural purposes and evidently are caused by applications of radioactive fertilizer. Third, anomalies of intermediate to low intensity are associated with heavy-mineral deposits. Results of this study show that aeroradiometric anomalies associated with heavy-mineral accumulations in the Coastal Plain of Virginia have ground radiometric spectra in which thorium is the strongest component and uranium and potassium are lesser components. Heavy-mineral accumulations found in this study by use of the aeroradiometric data are not considered to be of economic importance, mostly because of the low percentage of economic minerals in the heavy-mineral suites and also because of other factors such as the very fine grained nature of the host sediments and competing land use.

Virginia↗

Mineral resources of the Craggy Mountain Wilderness Study Area, Buncombe County, North Carolina

The Craggy Mountain Wilderness Study Area covers about 550 hectares of the Pisgah National Forest in the Blue Ridge Mountains of western North Carolina (fig. 1). The area is 21 km northeast of Asheville, Buncombe County, N.C., and 11 km southwest of Mount Mitchell, the highest point in eastern North America. The study area is bounded on the southeast by the Blue Ridge Parkway, on the northeast by Bullhead Ridge, and on the southwest and west by Big Fork Ridge (Plate 1b). It includes all of the Craggy Mountain scenic area established by the Forest Service in 1961 and some additional land west of Bearwallow Branch and along the middle part of Carter Creek for a short distance beyond the mouth of Peach Orchard Creek.

North Carolina↗